Explaining the individual processes leading to adaptive comfort: Exploring physiological, behavioural and psychological reactions to thermal stimuli

Behavioural, physiological and psychological adaptive processes are presumed reasons for the discrepancies between predicted mean vote and observed comfort votes during field studies. However, few are known about the individual portions of these processes. An experimental design was developed, which aims at identifying those portions and is meant for climate chambers with operable windows facing the exterior. This article looks in detail at behavioural and physiological reactions together with their effect on the perceived level of comfort. By means of multivariate regression analyses, these reactions are analysed in order to assess differences due to variations in indoor/outdoor conditions as well as the number of interactive opportunities. One of the results shows that the restriction to keep the window closed is counterbalanced by an increased amount of physiological reactions, such as an increased level of skin temperature, together with an increase of still permitted actions such as drinking. The results highlight the importance of detailed insights into single aspect of adaptive processes for a better understanding of the phenomenon called 'adaptive comfort'. Such approach is novel and important because a detailed knowledge and quantification of the occupant's comfort perception in naturally ventilated buildings permits a planning with less uncertainty.